Morse taper arbours in drill presses

**Dick** · 19-02-2023, 21:03

A particular feature of drill presses is bad design in my view, particularly those made for amateur use. My little workshop is a small room in the back of my nephew’s motor workshop. In my workshop I have a little Ryobi hobby drill press. There is another of different make but otherwise similar lying unused in the main car workshop, and a much bigger one in use in the main car workshop. All chucks (as far as I know) are fitted to drill presses with morse taper arbours. To be more precise an arbour with a male morse taper matching the female morse taper socket in the drill press quill and a shorter Jacobs taper the other end matching the female in the chuck. The size of both tapers relates to the size of the drill press and chuck. In small hobby drill presses the MT is usually No2 and the JT No2 as both these small presses are. The female MT socket in the big press is No3 but it is being use with a MT3 – MT2 adaptor sleeve. That’s important for reasons I’ll come to later.

I need to use a tapping head with one of the presses. Preferably with the small press in my workshop. But all attempts to get the arbour out of the press were unsuccessful. There is in fact no way to get them out of a hobby drill press if the chuck comes off without bringing the arbour with it. The bigger industrial presses have a pair of slots about 8 x 25mm in the quill, one each side at a distance above the bottom to allow a steel wedge to be inserted to knock out the arbour. But in this industrial press the slots are too low and are completely blocked by the MT3-MT2 adaptor. How stupid is that?

My attempt to pull the arbour out of my hobby press resulted in pulling off the chuck but leaving the arbour in the quill. “That’s OK” I thought, “I can fit the tapping head to the JT that’s poking out of the quill.” But no such luck – the arbour is JT No2 but the socket in the tapping head is No6.

So I have no choice but to use the industrial machine in the main workshop. My nephew knocks the drill chuck out, with its arbour, with a block of wood and a hammer. At least the arbour comes out with the chuck and doesn’t remain stuck in the machine. The problem is that the workshop crew occasionally uses the drill press for drilling holes, and if I leave my expensive tapping head in the machine overnight and the crew removes it by hammering it out before I arrive the following morning they’ll destroy it. That’s because the top portion of it is a rotating collar that sets the torque. Therefore I will have to remove the drill chuck before I can work, and remove my tapping head at the end of the day.

I have therefore made most of an extraction tool but don’t know if it will work until I test it. I’ll report back when I’ve tested it.

The best way to deal with this problem is to cut slots in quills that don’t have them and recut them if they are in the wrong position, for easy arbour removal by wedge. But that involves disassembling the press. And in the case of hobby presses, shortening the arbour because the quill doesn’t protrude far enough otherwise. As I said, lousy design. Hobby drill presses at least should have threaded quills and chucks for easy removal. If I could get the arbour out of my hobby press, I’d machine a MT2 arbour with a threaded bottom end and solder it into the quill, or glue it with Pratley’s steel epoxy. Or cross pin it.

**atunguyd** · 19-02-2023, 21:13

Can you not drill and tap the jt end of the arbor then put a threaded bar into it. Then place something like a socket over the arbor with the threaded rod golf right height it. Apply a nut and tighten to pull the arbor out.

Mt3 to mt2 adaptors that I have seen have a cutout on the sides which allow you to use the wedge method. If course this requires that you insert it aligned with with the slots in the the quill

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**Aceofspades** · 20-02-2023, 09:20

Hi Dick

My cheap little drillpress is a straight shaft that splines / keys through the pulley's bush. At the botom I just have the B taper onto the jacobs chuck.

If you do have a taper mount onto the spindle itself, the morse should let go before the B. Unfortunately things don'n always work out the way you want.

Slightly heat up the spindle shaft and maybe try penetrating fluid to get the morse out. If you have a blind hole the penetrating fluid might seal ot up though. Then you have to fight the vacuum as well.

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**janfred** · 20-02-2023, 11:14

Mine has a bolt on top in the spindle. I unscrew that a few turns, tap on the bolt with a hammer then the taper drops out.

**A-R** · 20-02-2023, 19:29

What is the spindle diameter?

If there is enough meat, you could drill it out so a narrow punch from the top can dislodge your MT.

**atunguyd** · 20-02-2023, 20:27

My idea of drilling and tapping the arbor is much safer. If you screw it up an arbor is a cheap replacement. A quill not so much!

Also arbors are not hardened so easy to drill.

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**Dick** · 22-02-2023, 19:53

Originally Posted by atunguyd

Can you not drill and tap the jt end of the arbor then put a threaded bar into it. Then place something like a socket over the arbor with the threaded rod golf right height it. Apply a nut and tighten to pull the arbor out.

Mt3 to mt2 adaptors that I have seen have a cutout on the sides which allow you to use the wedge method. If course this requires that you insert it aligned with with the slots in the the quill

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Tapping the JT end should work well. But right now the chuck came off leaving the arbour in the quill. It wouldn't be impossible to figure out a way to drill and tap it from underneath but awkward. I have a suspicion that it's like Aceofspades says, that what I have is a spindle inside the quill with the JT at the bottom ie not extractable.

I think you've hit the truth about not being able to use a wedge in the big drill press quill - the 3-2 MT adaptor is blocking the slots and I wouldn't be surprised that the guy who knocked in the adaptor good and tight didn't worry about lining up the slots in the adaptor with the slots in the quill.

The situation seems to be that I'll have to use the big drill press. I've made an extraction tool which I'm presently testing and improving. I'll post what I've done if and when it's satisfactory.

**Dick** · 22-02-2023, 19:54

Originally Posted by janfred

Mine has a bolt on top in the spindle. I unscrew that a few turns, tap on the bolt with a hammer then the taper drops out.

You are fortunate. I haven't seen one like that.

**Dick** · 22-02-2023, 19:58

Originally Posted by A-R

What is the spindle diameter?

If there is enough meat, you could drill it out so a narrow punch from the top can dislodge your MT.

Also a good idea, except that you can only drill right through a spindle in a lathe, for wich I'd have to disassemble the drill press. And deep hole drilling like that is a slow process. If I had time on my hands I'd consider stripping my small press and doing it. But right now the imperative is to get prepared to do the work which is imminent, so I have to do what's easiest.

**atunguyd** · 23-02-2023, 06:23

Originally Posted by Dick

Tapping the JT end should work well. But right now the chuck came off leaving the arbour in the quill. It wouldn't be impossible to figure out a way to drill and tap it from underneath but awkward. I have a suspicion that it's like Aceofspades says, that what I have is a spindle inside the quill with the JT at the bottom ie not extractable.

.

If you lie the drill press on its side and swing by the table or of the way it should be quite possible to do this with a cordless drill and a hand tap. Hell you could even turned the press upside down and test it on the belt cover.

You don't need the tapped hole to be perfectly vertical like a mill or drill press would give you and you can scrap the arbor afterwards as they are cheap to replace.

Actually as I type this I realised that you do have a drill press to do this in. The one you are trying to fix. Put a 5mm drill bit in the vise pointing straight up and align it more or less with the center of the arbor.

Switch on the drill and lower the spinning arbor onto the drill bit. It will be just like drilling with the tailstock of the lathe.

Tap hole to M6, put a M6 bolt through an appropriately sized socket and use this to pull the arbor out.

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